College of Liberal Arts

University of Mississippi

The DM: Oxford Science Café Highlights UM Involvement in Gravity Discoveries

Marco Cavaglia, associate professor of physics and astronomy and assistant spokesperson of the LIGPO Scientific Collaboration, explains he detection of gravitational waves at the Lusa Café Tuesday night. Photo by Taylor Cook

Marco Cavaglia, associate professor of physics and astronomy and assistant spokesperson of the LIGPO Scientific Collaboration, explains he detection of gravitational waves at the Lusa Café Tuesday night. Photo by Taylor Cook

February 17, 2016  |  By Kelsey Sims for The Daily Mississippian

It’s not often that scientists discover something new about something as well known as gravity, but then again, Einstein predicted this 100 years ago.

Last week, scientists from the Laser Interferometer Gravitational-Wave Observatory announced they finally detected gravitational waves from the convergence of two black holes at two different research facilities in Hanford, Washington and Livingston, Louisiana.

Katherine Dooley, assistant professor of physics and astronomy, and Marco Cavaglià, associate professor of astronomy and physics, and a group students and research assistants, are a part of the organization that made this discovery.

Tuesday evening at Lusa Bakery Bistro and Bar, Dooley and Cavaglià participated in the Oxford Science Café, a monthly meeting held to talk about important developments and issues in various scientific fields.

Their presentation, titled “Observation of Gravitational Waves from a Binary Black Hole,” discussed how the LIGO Collaboration made this discovery after a century of trying to prove the existence of gravitational waves.

The small bakery was packed with not only members of the Oxford community, but also people from locales ranging from Southern Mississippi to Italy.

Sophomore accounting major Duncan Ploetz showed a particular enthusiasm for the subject.

“I’ve been interested in astrophysics since high school,” Ploetz said. “I guess I wanted to meet the people that made the discoveries before they are written down in books.”

The University of Mississippi branch of the LIGO began in 2007 with Cavaglià as its founder.

“I got involved in LIGO about eight or nine years ago when I moved to Ole Miss,” Cavaglià said. “At that time, I was doing gravitational studies, but more on black holes and cosmic rays. But when I moved here, I got interested in the LIGO experiment.”

During the presentation, Cavaglià discussed how gravitational waves were created by the combination of two black holes.

“Basically, we have one black hole weighing 36 solar masses and another that’s a little bit smaller, weighing 29 solar masses,” Cavaglià said. “When they come together, you would think the black hole would weigh 65 solar masses, but it only weighed 62. This means that 3 times what the sun weighs of energy got released in the form of gravitational waves.”

He went on to say LIGO uses a interferometer to detect the stretches in space-time with light. This machine was the first component of UM-LIGO’s part in the discovery of gravitational waves.

Dooley began working with the interferometers during a fellowship at California Technical Institute, one of the main research facilities that took part in this discovery. Dooley specialized in researching ways to improve their technology to make it more sensitive to gravitational waves.

About six months ago, Dooley came to Ole Miss and joined Cavaglià at UM-LIGO.

“The University was looking for an experimentalist in gravitational research, and that fits my background,” Dooley said.

The second component was data analysis that Cavaglia called “detector characterization.” He and a senior physics major, Hunter Gabbard, deal with this aspect of the project.

“I mainly study seismic noise and create algorithms to predict when things like earthquakes will happen,” Gabbard said. “This is so we can tell when something will interfere with the detection of gravitational waves.”

Gabbard began studying with UM-LIGO his freshman year under Cavaglia and has since been part of fellowships in Paris and the University of Texas Rio Grande Valley. He also collaborated with Dooley to write their paper on this discovery.

This discovery has opened many doors for future study of space and gravity.

“We hope that this discovery will lead to more detections in the future,” Cavaglià said. “Hopefully, it will eventually be on a daily basis.”

Dooley shared her enthusiasm for future detections, saying it might be possible to eventually figure out the composition of neutron stars because of this discovery.

“I hope (this discovery) inspires more students to enter science,” Dooley said. “It’s been really fun to see the response from the public so far, how it’s captivated everyone.”